Makes sense within the game world. Everyone is out to train their little pocket monsters in the game world too, so I could see it. I think it would be a nightmare to oversee though. And yeah, I could see people getting really pissed if the franchise tried to do anything too different.

Plus it has more or less become a competitive sport to a certain degree. If they change up the mechanics now it'd be like making the transition from the GB/C to GBA which to some people would be an inexcusable waste of the time spent over the last decade in making their tweeked out murder teams full of ribbons, shinnies, and event exclusives.

The single player mode at this point is more of a feature and a source for more grinding, catching, breeding, award-winning, and accessorizing opportunities.

Pokemon is the biggest Not-MMO MMORPG in existence, and I dare say bigger than WoW.

"Enterbrain and Famitsu have provided a first week sales figure for Pokemon Black & White 2. The DS sold 1,618,621 in its first week of sales. As the game was released on a Saturday, the "first week" includes just two days." -- Source: andriasang

A few weeks ago I interviewed the directors of Black 2/White 2 for IGN and kind of sort of found out a few things about the idea behind creating direct sequels, and the future of the series (I wasn't allowed to directly ask about future projects, so no questions about a Pokemon MMO, sadly). Anyway, here's the article: http://uk.ign.com/articles/2012/09/19/pokemon-will-eat-itself

I took a break from Pokemon, and then picked up Black 1 and really enjoyed it. I only got an hour and a half with Black 2, and it does largely seem like more of the same. I did get horribly overexcited when a wild Psyduck popped up within the first half hour though :P